T-Cell lymphoproliferative disorder of hand-mirror cell morphology presenting in an eosinophilic loculated peritoneal effusion, with omental "caking.".

Background: Cells with "hand mirror" morphology have not, to the best of our knowledge, been described in a primary effusion sample. This paper describes a case of T-cell lymphoma with eosinophilia in a patient with suspected peritoneal carcinomatosis. Rarely, a T-cell lymphoproliferative process may mimic primary peritoneal carcinomatosis, clinically suggested by a presentation in CT imaging of omental caking with bilateral massive loculated effusions in a patient without lymphadenopathy or splenomegaly. Methods: A 60 year old caucasian male presented with vague abdominal discomfort and increasing abdominal girth. Computed tomography showed a two centimeter thick omental cake and a small loculated effusion. The clinical presentation and imaging findings were most consistent with peritoneal carcinomatosis. Cytologic evaluation of the effusion was undertaken for diagnostic study. Results: Rapid intraprocedural interpretation of the effusion sample showed a monomorphic population of cells with "hand-mirror" cell morphology exhibiting cytoplasmic extensions (uropodia) with 3-5 course dark cytoplasmic granules and a rim of vacuolated cytoplasm capping the opposing "mirror head" side. These cells were seen within a background of mature eosinophils. Flow cytometric evaluation of the ascites fluid demonstrated an atypical T-cell population with the following immunophenotype: CD2-, CD3+, CD4-, CD5-, CD7-, CD8+, CD56+. T-cell receptor (TCR) gene rearrangement was positive for clonal TCR-gamma gene rearrangement, supporting the diagnosis of a T-lymphoprolifereative disorder. Conclusion: A T-cell lymphoproliferative process may present with "hand mirror" morphology in an effusion sample. These cells may show polar cytoplasmic vacuolization and 3-5 course granules within the "handle" of these unique cells. Cytoplasm shows peripheral constriction around the nucleus. [ABSTRACT FROM AUTHOR]